Set-screw.



H. G. HART.

SET SCREW.

APPLICATION nun MAY 6. 1910.

1,061,176. Patented Mayfi, 1913.

witnesses a H l A 6'4, Lduzan HUBER'J. c. Ii-ART, onnNroNvuLn,CONNECTICUT.

SET-SCREW.

Specification of Letters Patent.

Patented May 6, 1913.

Application filed May 6, 1910. Serial No. 559,777.

To all whom it may concern:

Be it known that I, HUBERT C; HART, a citizen of the United States,residing at Unionville, in the county of Hart-ford and State ofConnecticut, have invented certain new and useful Improvements in Set-Screws; and I do herebydeclare the following to be a full, clear, andexact description of the invention, such as will enable others skilledin the art to which it appertains to make and use the same, referencebeing had to the accompanying drawings, and to let I a set screw, andthe vertical section of the same.

ters or figures of reference marked thereon, Which'form a part of thisspecification.

This invention relates to improvements in method of making the same.

Heretofore in the manufacture of set screws, it has been necessary toprovide a piece of metal equal to the greatest diameter of the proposedhead of the screw and turn it thread the stem. This process is not onlyexpensive, but is tedious andslow. The oss of material in shaping thescrew is wasteful, which also adds to the cost of pro duction.

According to my invention I first-.form a head or cap from sheet metal,then cup and shape the Same as may be found most convenient. In thebottom of the cap or head when in the course of manufacture, a seat isformed to receive a screw or small bolt,the same being rigidly fixed tothe cap in such manner as will prevent it becoming disengaged when inpractical use.

The invention also relates to improvements in the details ofconstruction and arrangement of parts Which will be hereinafterdescribed and particularly pointed out in the claim.

In the drawings :-Figure 1 is a View of a blank from which the cap orhead is formed. Fig. 2 is a conventional illustration of the manner ofcupping or shaping the cap.- Fig. 3 is a- -view illustrating the mannerof-forming the head at the top of the cap. Fig. 4 is a detailperspective view of the completed set screw. Fig. 5 is a Fig. 6 is aView of a slightly different form of the invention.

The numeral 1 indicates a roundblank from which the cap or head(hereinafter termed cap) is formed. The blank 1 is drawn up intosubstantially cup shape in down in proper shape, and thencross section,as shown in Fig. 2, and is then reversely cupped to form the upper head3, as shown in F i'g. 3. The outer edge of the head is knurled, and inthe flat base or bottom is formed a square opening 5.

After the cap is finished I secure thereto a bolt or screw'having a head7, a square portion 8, and threaded stem 9. The bolt is inserted throughthe top of the cap, and the head rests on the upper surface of the flatbottom, the square port-ion 8, fitting snugly in the opening 5. Theshape of the portion 8, and the opening 5, will necessarily prevent thecap turning independently of the bolt, but to insure a rigid connectionbetween the two elements, the bottom edges of the square portion areswaged or flattened to prevent the bolt slipping through the opening.Hence by this construction the bolt and cap are effectually securedtogether against independent turning or displacement. In other words theca 1) and bolt become a unit.

In the modification shown in Fig. 6, the bottom of the cap is elevatedat the center and is formed with a threaded openin 10, to receive thethreaded end of the olt. This construction will afford a tight andsecure joint between the cap and bolt, however, I prefer the structurepreviously described.

A set screw constructed as described is considerably less expensive tomanufacture than the means heretofore employed and substantially thesame results are accomplished.

I find in actual practice that set screws made in accordance with myinvention results in a saving of about two hundred (200) per cent. Furthermore, the convenience and simplicity of the manufacture of thecaps, enables me to save considerable time, which I regard as a vitalimportance.

The head formed at the upper end of the cap serves to strengthen thestructure, and especially precludes the possibility of the upper edge ofthe cap being crushed or collapsing when in use.

What I claim is:

A new article of manufacture comprisin a cupped cap formed of sheetmetal, the sai cap having a fiat bottom formed wlth an opening, thewalls of which are angular, the lower portion of the walls of the capbein substantially vertical and annular an flare outwardly from theannular portion, and

\an angular portion fitting against the angular walls of the opening,and the threaded portion being of less] thence the said walls curveinwardly and form an annular bead to provide a finger grip, the top ofthe'cap being open, and a headed screw fitting in the opening in thebottom of the cap, the head of the screw being of less width than thediameter of the opening formed bet-Ween the edges of the cap forming thebead, said screw having to correspond with and 'the bottom of said cap.

diameter than the width of the opening in the bottom of the cap andextending below In testimony whereof I have signed my 15 name to thisspecification in the presence of two subscribing Witnesses.

HUBERT o. HART.

Witnesses:

NELLIE MI HART, WILLIS 0. HART.

